Biopolym. Cell. 2020; 36(2):110-121.
http://dx.doi.org/10.7124/bc.000A25
Structure and Function of Biopolymers
Alterations in expression of S6K1 isoforms in MCF7 cells have a strong impact on the locomotor activity as well as on S6K1 and Akt signaling
1Kosach V. R., 1Hotsuliak N. Ya., 1Zaiets I. V., 1Skorokhod O. M., 1Savinska L. O., 1Khoruzhenko A. I., 1Filonenko V. V.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03143

Abstract

Aim. To generate and characterize MCF-7 cell lines with altered expression of p85, p70 and p60 S6K1 isoforms: p85-/p70-/p60-MCF-7 and p85-/p70-/p60+MCF-7. Methods. CRISPR/Cas9 gene editing, western blot analysis, immunofluorescence analysis, scratch assay. Results. Modified MCF-7 cells with knocked down expression of p85, p70, p60 or only p85 and p70 S6K1 isoforms were generated. Selective inhibition of only p85 and p70 isoforms in p85-/p70-/p60+MCF-7 cellswas accompanied by actin cytoskeleton rearrangements, appearance of fibroblast-like cell morphology and significantly increasedcell locomotor activity. Downregulation of all three S6K1 isoforms in p85-/p70-/p60 – MCF-7 cells inhibited cell migration with no changes in the cell morphology. Alterations inhad a different impact on the ribosomal protein S6 phosphorylation and Akt signaling. Conclusion. Analysis of the modified MCF-7 cell lines revealed different impact of expression of S6K1 isoforms on MCF7 cell locomotor activity and the S6K1– and Akt-dependent signaling. Our data suggest that p60-S6K1 could be involved in regulation of the cell migration. The generated cells can be used for furtheranalysis of functionalactivity of the S6K1 isoforms.
Keywords: mTOR/S6K1 signaling, MCF-7, S6K1, CRISPR/Cas9, breast cancer
Full text: (PDF, in English)

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